Machines, such as hydraulic excavators and hydraulic shovels, perform work at a work site. Among the work performed, the machines are employed to raise a load from a loading location and dump the load at a dumping location. For the purpose of handling such a load, the machines employ a work tool, such as a bucket, coupled to a boom assembly via a stick of the machine. The boom assembly includes a boom coupled to the stick and multiple hydraulic actuators to enable pivotal movement of the stick. Further, the boom is pivotally coupled to a frame of the machine to allow travel of the work tool to a desired height or depth. Typically, the boom is formed from steel. Although steel provides structural stability to the boom, steel renders the boom heavy. In cases where the machine includes a long boom, the weight of the boom may be higher than desired. In addition, such a long boom may often be subjected to dipping, where the frame of the machine tends to lift from ground surface when the boom lifts heavy loads. As such, the weight of the boom becomes detrimental to operation of the machine, thereby restricting optimization of boom design. Further, when different operations of the machine create different loads, it would be desirable to modify the ability of the boom to accommodate to the different loads.
Chinese Patent Application Number 103332610 describes a connection structure of an end part of a cantilever, which is made of carbon-fiber composite materials. The connection structure is formed by successive adhesion of metal and carbon-fiber, where a metal internal layer is the inner part, a metal outside plate is the outer part, and a carbon-fiber enhanced layer is arranged between the inner part and the outer part. The metal internal layer and the metal outside plate are connected by welding, and form a sandwich structure. The metal inner layer includes a long metal tube, two short metal tubes, and a frame. One end of the frame is provided with a square component, and the other end of the frame is provided with a U-shaped connector.